Option market activity increases by more than 10 percent in the four days before quarterly earnings announcements. We show that the direction of this preannouncement trading foreshadows subsequent earnings news. Specifically, we find option traders initiate a greater proportion of long (short) positions immediately before “good” (“bad”) earnings news. Midquote returns to active‐side option trades are positive during nonannouncement periods and are significantly higher immediately prior to earnings announcements. Bid‐ask spreads for options widen during the announcement period, but traders do not gravitate toward high delta contracts. Collectively, the evidence shows option traders participate generally in price discovery (the incorporation of private information in price), and more specifically in the dissemination of earnings news.

We use an extension of the equilibrium framework of Rubinstein (1976) and Brennan (1979) to derive an option valuation formula when the stock return volatility is both stochastic and systematic. Our formula incorporates a stochastic volatility process as well as a stochastic interest rate process in the valuation of options. If the “mean,” volatility, and “covariance” processes for the stock return and the consumption growth are predictable, our option valuation formula can be written in “preference-free” form. Further, many popular option valuation formulae in the literature can be written as special cases of our general formula.

We use an extension of the equilibrium framework of Rubinstein ( 1976 ) and Brennan ( 1979 ) to derive an option valuation formula when the stock return volatility is both stochastic and systematic. Our formula incorporates a stochastic volatility process as well as a stochastic interest rate process in the valuation of options. If the “mean,” volatility, and “covariance” processes for the stock return and the consumption growth are predictable, our option valuation formula can be written in “preference‐free” form. Further, many popular option valuation formulae in the literature can be written as special cases of our general formula.